Communication apparatus, terminal apparatus, image processing system, and communication method

ABSTRACT

A communication apparatus includes a first communication unit, a second communication unit, and a communication-apparatus-side controller. The first communication unit wirelessly communicates with plural terminal apparatuses, the number of which is less than or equal to a predetermined maximum number of connections allowed. The second communication unit wirelessly communicates with a connection-requesting terminal apparatus that attempts to wirelessly communicate with the first communication unit. The communication-apparatus-side controller transmits, to the connection-requesting terminal apparatus via the second communication unit, information indicating that wireless communication via the first communication unit is not available in a case where the number of connections established for wireless communication via the first communication unit has reached the predetermined maximum number of connections allowed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based on and claims priority under 35 USC 119 fromJapanese Patent Application No. 2014-138903 filed Jul. 4, 2014.

BACKGROUND

(i) Technical Field

The present invention relates to a communication apparatus, a terminalapparatus, an image processing system, and a communication method.

(ii) Related Art

For example, there are cases where a user wishes to connect a terminalapparatus to a communication apparatus by using wireless communicationbased on Wireless Fidelity (Wi-Fi) or the like. In such cases, theterminal apparatus and the communication apparatus may be automaticallyand easily connected to each other by causing the terminal apparatus totransmit and receive connection conditions via wireless communicationsuch as near-field communication (NFC) in advance.

SUMMARY

According to an aspect of the invention, there is provided acommunication apparatus including a first communication unit, a secondcommunication unit, and a communication-apparatus-side controller. Thefirst communication unit wirelessly communicates with plural terminalapparatuses, the number of which is less than or equal to apredetermined maximum number of connections allowed. The secondcommunication unit wirelessly communicates with a connection-requestingterminal apparatus that attempts to wirelessly communicate with thefirst communication unit. The communication-apparatus-side controllertransmits, to the connection-requesting terminal apparatus via thesecond communication unit, information indicating that wirelesscommunication via the first communication unit is not available in acase where the number of connections established for wirelesscommunication via the first communication unit has reached thepredetermined maximum number of connections allowed.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention will be described indetail based on the following figures, wherein:

FIG. 1 illustrates an example of an overall configuration of an imageprocessing system according to an exemplary embodiment;

FIG. 2 illustrates an example of a hardware configuration of an imageprocessing apparatus;

FIG. 3 illustrates an example of a hardware configuration of a mobileterminal;

FIG. 4 is a block diagram illustrating an example of functionalconfigurations of the image processing apparatus and the mobileterminal;

FIG. 5 is a flowchart describing operations performed by the imageprocessing apparatus and the mobile terminal in a first exemplaryembodiment;

FIG. 6 is a flowchart describing operations performed by the imageprocessing apparatus and the mobile terminal in a second exemplaryembodiment;

FIG. 7 is a flowchart describing operations performed by the imageprocessing apparatus and the mobile terminal in a third exemplaryembodiment; and

FIG. 8 is a flowchart describing operations performed by the imageprocessing apparatus and the mobile terminal in a fourth exemplaryembodiment.

DETAILED DESCRIPTION

Exemplary embodiments of the present invention will be described indetail below with reference to the accompanying drawings.

System Configuration

An overall configuration of an image processing system 1 according to anexemplary embodiment will be described. FIG. 1 illustrates an example ofan overall configuration of the image processing system 1 according tothe present exemplary embodiment. As illustrated in FIG. 1, the imageprocessing system 1 includes an image processing apparatus 10A, an imageprocessing apparatus 10B, a mobile terminal 20A, a mobile terminal 20B,a mobile terminal 20C, an operation terminal 30A, an operation terminal30B, and a management server 40. Wireless communication is performedamong the image processing apparatus 10A, the image processing apparatus10B, the mobile terminal 20A, the mobile terminal 20B, and the mobileterminal 20C. In addition, the image processing apparatus 10A, the imageprocessing apparatus 10B, the operation terminal 30A, the operationterminal 30B, and the management server 40 are connected to a network 50and communicate with one another via the network 50.

The image processing apparatuses 10A and 10B are illustrated in FIG. 1;however, the image processing apparatuses 10A and 10B are referred to asimage processing apparatuses 10 if distinction between them is notrequired. Likewise, the mobile terminals 20A, 20B, and 20C areillustrated in FIG. 1; however, the mobile terminals 20A, 20B, and 20Care referred to as mobile terminals 20 if distinction between them isnot required. Further, the operation terminals 30A and 30B areillustrated in FIG. 1; however, the operation terminals 30A and 30B arereferred to as operation terminals 30 if distinction between them is notrequired. Two image processing apparatuses 10 are provided in theexample illustrated in FIG. 1; however, three or more image processingapparatuses 10 may be provided. Further, three mobile terminals 20 areprovided in the example illustrated in FIG. 1; however, four or moremobile terminals 20 may be provided. In addition, two operationterminals 30 are provided in the example illustrated in FIG. 1; however,three or more operation terminals 30 may be provided.

Each of the image processing apparatuses 10 is, for example, anapparatus having functions such as a scan function, a print function, acopy function, and a facsimile function, and forms an image on arecording medium such as paper and outputs the resulting recordingmedium. Each of the image processing apparatuses 10 receives a print jobfrom the mobile terminals 20 and the operation terminals 30 and performsa printing process in accordance with the print job that has beenreceived. A print job includes image data to be printed and a controlinstruction that describes settings used in the printing process, and isdata that serves as a unit of a printing process performed by the imageprocessing apparatus 10.

Each of the mobile terminals 20 is a mobile computer apparatus used whenan instruction to execute various functions is given to the imageprocessing apparatuses 10. For example, an apparatus such as asmartphone, a tablet personal computer (PC), or a notebook PC may beused as the mobile terminal 20.

Each of the operation terminals 30 is a computer apparatus used by auser to view and edit a document file. For example, an apparatus such asa notebook PC or a desktop PC may be used as the operation terminal 30.In addition, a mobile computer apparatus such as a smartphone may alsobe used as the operation terminal 30.

The management server 40 is a computer apparatus that stores variouskinds of data processed by the image processing system 1.

The network 50 is a communication medium used for communication ofinformation among apparatuses such as the image processing apparatuses10, the operation terminals 30, and the management server 40. Thenetwork 50 is, for example, a wired local area network (LAN).

In the present exemplary embodiment, short-range wireless communication(e.g., NFC) and wireless communication based on another communicationstandard (e.g., Wi-Fi Direct (registered trademark)) that achieves aspeed higher than that achieved with the short-range wirelesscommunication are performed between the image processing apparatuses 10and the mobile terminals 20. NFC is a wireless communication standard inwhich a communication range is limited to approximately ten centimeters.In addition, Wi-Fi Direct is a standard that enables directcommunication between Wi-Fi (registered trademark) terminals. Accordingto Wi-Fi Direct, each Wi-Fi device has a function for operating as anaccess point. An access point is a relay device that wirelessly relayscommunication between devices. Specifically, according to Wi-Fi Direct,one of plural Wi-Fi devices that participate in a network substantiallyoperates as an access point, and direct communication is performedbetween the device serving as the access point and the other Wi-Fidevices.

According to Wi-Fi Direct, each communication apparatus thatparticipates in a certain network is defined as a peer-to-peer (P2P)device, and the network is defined as a P2P group. A P2P device thatsubstantially operates as an access point in a P2P group is defined as aP2P group owner. P2P devices other than the P2P group owner are definedas P2P clients. Each P2P device exchanges a signal with another P2Pdevice to detect a P2P device that serves as a Wi-Fi Direct connectiondestination candidate. In this way, the P2P group owner is selected fromamong plural P2P devices.

In the present exemplary embodiment, a description will be given on theassumption that the image processing apparatuses 10 serve as the P2Pgroup owners. In addition, according to Wi-Fi Direct, a maximum numberof P2P clients that are allowed to connect to the P2P group owner at onetime is generally set. In the present exemplary embodiment, it isassumed that the maximum number for the number of mobile terminals 20that are allowed to connect to each of the image processing apparatuses10 using Wi-Fi Direct at one time (hereinafter, referred to as thenumber of simultaneous connections) is three.

Hardware Configuration of Image Processing Apparatus 10

A hardware configuration of the image processing apparatus 10 will bedescribed next. FIG. 2 illustrates an example of a hardwareconfiguration of the image processing apparatus 10. As illustrated inFIG. 2, the image processing apparatus 10 includes a central processingunit (CPU) 101, a random access memory (RAM) 102, a read only memory(ROM) 103, a hard disk drive (HDD) 104, an operation panel 105, an imageforming unit 106, an image scanning unit 107, an image processing unit108, a wired communication interface (I/F) 109, a wireless communicationI/F 110, and an NFC I/F 111, which are connected to a bus 112 andexchange data with one another via the bus 112.

The CPU 101 executes various kinds of software such as an operatingsystem (OS) and applications. The RAM 102 is a memory that is used as,for example, a work memory of the CPU 101. The ROM 103 is a memory thatstores, for example, various programs to be executed by the CPU 101. TheCPU 101 loads the various programs stored in the ROM 103 or the likeinto the RAM 102 and executes the various programs so as to implementthe functions of the image processing apparatus 10.

The HDD 104 is, for example, a magnetic disk device that stores imagedata or the like used in an image forming operation performed by theimage forming unit 106.

The programs to be executed by the CPU 101 may be pre-stored in the ROM103 or may be provided after being stored on a computer readablerecording medium, such as a magnetic recording medium (such as amagnetic tape or a magnetic disk), an optical recording medium (such asan optical disc), a magneto-optical recording medium, or a semiconductormemory. Alternatively, the programs may be provided to the CPU 101 viathe network 50, for example.

The operation panel 105 is, for example, a touch panel that displaysvarious kinds of information and accepts an operation input from a user.The operation panel 105 includes a display that displays various kindsof information and a position detector sheet that detects a positiontouched with a finger or a stylus. Any detector, such as a detector thatdetects a touched position based on a pressure caused by the touch orbased on a static electricity of an object that has touched, may be usedto detect the touched position. In addition, a display and an inputdevice such as a keyboard may be used in place of the touch panel. Notethat the operation panel 105 need not be a touch panel.

The image forming unit 106 forms an image on a recording medium. Forexample, a printer such as an electrophotographic printer that transferstoner on a photoconductor onto a recording medium so as to form an imageon the recording medium or an inkjet printer that ejects ink onto arecording medium so as to form an image on the recording medium may beused as the image forming unit 106.

The image scanning unit 107 scans an image on a recording medium andgenerates image data representing the image that has been scanned. Theimage scanning unit 107 is, for example, a scanner such as of a chargecoupled device (CCD) system in which reflecting light of light that hasbeen radiated onto an original from a light source is size-reduced by alens and is received by CCDs or of a contact image sensor (CIS) systemin which reflecting light of light that has been sequentially radiatedonto an original from a light-emitting diode (LED) light source isreceived by a CIS.

The image processing unit 108 performs image processing such as colorcorrection and gradation correction on image data input thereto andgenerates image data that has undergone the image processing.

The wired communication I/F 109 functions as a communication interfacethat enables transmission and reception of various kinds of data to andfrom the operation terminals 30 and the management server 40 via thenetwork 50.

The wireless communication I/F 110 includes an antenna used for Wi-FiDirect wireless communication with the mobile terminals 20 and functionsas a communication interface that enables transmission and reception ofvarious kinds of data to and from the mobile terminals 20.

The NFC I/F 111 includes an antenna used for NFC communication with themobile terminals 20 and functions as a communication interface thatenables transmission and reception of various kinds of data to and fromthe mobile terminals 20.

Hardware Configuration of Mobile Terminal 20

FIG. 3 illustrates an example of a hardware configuration of the mobileterminal 20.

As illustrated in FIG. 3, the mobile terminal 20 includes a CPU 201 anda memory 202. The CPU 201 executes various kinds of software such as anOS and applications. The memory 202 includes a storage area in which thevarious kinds of software, data used for execution of the various kindsof software, and so on are stored.

Programs to be executed by the CPU 201 may be pre-stored in the memory202 or may be provided to the CPU 201 after being stored on a computerreadable recording medium, such as a magnetic recording medium (such asa magnetic tape or a magnetic disk), an optical recording medium (suchas an optical disc), a magneto-optical recording medium, or asemiconductor memory. Alternatively, the programs may be provided to theCPU 201 via the Internet, for example.

The mobile terminal 20 further includes a wireless communication I/F 203and an NFC I/F 204 that enable wireless communication between the mobileterminal 20 and an external device, and an image display unit 205 thatdisplays an image.

The wireless communication I/F 203 has a configuration and a functionthat are similar to those of the wireless communication I/F 110 (seeFIG. 2) of the image processing apparatus 10. In addition, the NFC I/F204 has a configuration and a function that are similar to those of theNFC I/F 111 (see FIG. 2) of the image processing apparatus 10.

The image display unit 205 is, for example, a touch panel. Accordingly,the image display unit 205 includes a liquid crystal panel and aposition detector (not illustrated) that detects a position of theliquid crystal panel that is touched by an object such as a human fingeror a stylus when the liquid crystal panel is touched by the object. Thetouch panel used in the present exemplary embodiment is not limited toany particular type, and a touch panel of any given type such as aresistive film type or an electrostatic capacitive type may be used.

The mobile terminal 20 may include, for example, an HDD or a flashmemory as a memory. An HDD or a flash memory stores data to be input tovarious kinds of software and data output from the various kinds ofsoftware, for example. The mobile terminal 20 may further include aninput device, such as a keyboard or a mouse.

In the above-described image processing system 1, the mobile terminals20 and the operation terminals 30 transmit a print job to the imageprocessing apparatuses 10 via the network 50 or Wi-Fi Direct wirelesscommunication. In this way, printing is performed by the imageprocessing apparatuses 10.

The management server 40 is capable of managing print jobs to beexecuted by the image processing apparatus 10, rearranging the printjobs in an appropriate order, and transmitting the print jobs to theimage processing apparatus 10. In this case, the management server 40functions as a print server. The management server 40 is capable ofmanaging files so as to allow the files to be shared among the mobileterminals 20 and the operation terminals 30. In this case, themanagement server 40 functions as a file server.

In the present exemplary embodiment, there are two methods forconnecting the mobile terminal (terminal apparatus) 20 to the imageprocessing apparatus 10 by using Wi-Fi Direct.

One method is a method in which the mobile terminal 20 is operateddirectly to connect the mobile terminal 20 to the image processingapparatus 10. According to this method, a user of the mobile terminal 20causes the mobile terminal 20 to display access points currentlyavailable for connection on the image display unit 205, for example.Then, the user selects a service set identifier (SSID) corresponding tothe image processing apparatus 10 from among the displayed access pointsand inputs a password or the like. After the user has beenauthenticated, a connection is established. Note that authentication isnot requested in some cases.

The other method is a method that uses the NFC I/F 111. According tothis method, a user of the mobile terminal 20 pre-sets connectionconditions in order to connect the mobile terminal 20 to the imageprocessing apparatus 10 by using Wi-Fi Direct. The NFC I/F 204 of themobile terminal 20 and the NFC I/F 111 of the image processing apparatus10 wirelessly communicate with each other so as to transmit theconnection conditions to the image processing apparatus 10. Thisconsequently causes the image processing apparatus 10 to performauthentication of the mobile terminal 20. In this way, the mobileterminal 20 is connected to the image processing apparatus 10 by usingWi-Fi Direct.

According to this method, the mobile terminal 20 and the imageprocessing apparatus 10 first use NFC to perform wireless communication,via which the connection conditions are transmitted and received by theNFC I/F 204 and the NFC I/F 111. After the mobile terminal 20 has beenauthenticated, the communication mode is switched from NFC to Wi-FiDirect (handover).

Thereafter, the mobile terminal 20 and the image processing apparatus 10wirelessly communicate with each other by using Wi-Fi Direct via thewireless communication I/F 203 and the wireless communication I/F 110,respectively. Specifically, the image processing apparatus 10 performswireless communication via the wireless communication I/F 110 instead ofthe NFC I/F 111 as a result of the handover. The mobile terminal 20performs wireless communication via the wireless communication I/F 203instead of the NFC I/F 204 as a result of the handover. That is, thismethod (NFC connection handover technology) causes the mobile terminal20 and the image processing apparatus 10 to be connected to each otherby using Wi-Fi Direct in response to the mobile terminal 20 being placedover or on the NFC I/F 111 of the image processing apparatus 10. Thismethod thus makes it easier for a user to establish a connection andimproves user friendliness.

However, as described above, the maximum number of mobile terminals 20that are allowed to connect to the image processing apparatus 10 is setwhen Wi-Fi Direct is used. In the above-described example, the maximumnumber is set to three. For this reason, if the number of mobileterminals 20 that are already connected to the image processingapparatus 10 has reached the maximum number of connections allowed inWi-Fi Direct when the mobile terminal 20 attempts to establish aconnection to the image processing apparatus 10, the new connection isnot allowed.

In the related art, the user of the mobile terminal 20 is not informedof such a situation and thus is kept waiting until a timeout occurs, forexample.

In contrast, in the present exemplary embodiment, the image processingapparatus 10 and the mobile terminal 20 are configured to have thefollowing functional configurations so as to inform a user of the mobileterminal 20 that no Wi-Fi Direct connection is available.

Description regarding Functional Configurations of Image ProcessingApparatus 10 and Terminal Apparatus 20

FIG. 4 is a block diagram illustrating an example of functionalconfigurations of the image processing apparatus 10 and the mobileterminal 20.

As illustrated in FIG. 4, the image processing apparatus 10 includes aWi-Fi connection unit 11, an NFC connection unit 12, acommunication-apparatus-side control unit 13, and an image forming unit14. The mobile terminal 20 includes a Wi-Fi connection unit 21, an NFCconnection unit 22, a terminal-apparatus-side control unit 23, and adisplay unit 24. Note that FIG. 4 selectively illustrates functionsrelated to the present exemplary embodiment from among various functionsof the image processing apparatus 10 and the mobile terminal 20. Inaddition, as illustrated in FIG. 4, the image processing apparatus 10may be considered as a communication apparatus in the present exemplaryembodiment.

The Wi-Fi connection unit 11, which is an example of a firstcommunication unit, is a functional unit that performs Wi-Fi Directwireless communication in the image processing apparatus 10. The Wi-Ficonnection unit 11 corresponds to the wireless communication I/F 110illustrated in FIG. 2. Specifically, the Wi-Fi connection unit 11 has afunction that enables transmission and reception of information viawireless communication to and from plural mobile terminals 20, thenumber of which is less than or equal to a predetermined maximum numberof connections allowed.

The NFC connection unit 12, which is an example of a secondcommunication unit, is a functional unit that performs NFC wirelesscommunication in the image processing apparatus 10. The NFC connectionunit 12 corresponds to the NFC I/F 111 illustrated in FIG. 2.Specifically, the NFC connection unit 12 has a function that enablestransmission and reception of information concerning connectionconditions via wireless communication to and from the mobile terminal 20(which is also referred to as a connection-requesting terminalapparatus) that attempts to wirelessly communicate with the Wi-Ficonnection unit 11. The information concerning connection conditions isused to establish a connection to the Wi-Fi connection unit 11 using thepre-set connection conditions. The information concerning connectionconditions transmitted from the mobile terminal 20 includes, forexample, a media access control (MAC) address or a serial number of themobile terminal 20. In addition, the information concerning connectionconditions transmitted from the image processing apparatus 10 includes,for example, a MAC address or an SSID of the image processing apparatus10.

The communication-apparatus-side control unit 13, which is an example ofa communication-apparatus-side controller, controls the Wi-Fi connectionunit 11, the NFC connection unit 12, and the image forming unit 14. Thecommunication-apparatus-side control unit 13 corresponds to acombination of the CPU 101, the RAM 102, the ROM 103, the HDD 104, andthe image processing unit 108 illustrated in FIG. 2.

The image forming unit 14 is a functional unit that forms an image. Theimage forming unit 14 corresponds to the image forming unit 106illustrated in FIG. 2. In the present exemplary embodiment, imageinformation used by the image forming unit 14 to form an image isreceived not by the NFC connection unit 12 but by the Wi-Fi connectionunit 11. That is, information transmitted or received by the Wi-Ficonnection unit 11 via wireless communication includes the imageinformation used by the image forming unit 14 to form an image. This isbecause Wi-Fi Direct generally has a higher communication speed than NFCand image information, which is likely to contain a large amount ofdata, is transmitted at a higher rate when Wi-Fi Direct is used thanwhen NFC is used.

The Wi-Fi connection unit 21, which is an example of a thirdcommunication unit, is a functional unit that performs Wi-Fi Directcommunication in the mobile terminal 20. The Wi-Fi connection unit 21corresponds to the wireless communication I/F 203 illustrated in FIG. 3.Specifically, the Wi-Fi connection unit 21 has a function that enablestransmission and reception of information to and from the imageprocessing apparatus 10 via a wireless communication network (a Wi-FiDirect communication network in this case) for which a maximum number ofconnections allowed is predetermined.

The NFC connection unit 22, which is an example of a fourthcommunication unit, is a functional unit that performs NFC communicationin the mobile terminal 20. The NFC connection unit 22 corresponds to theNFC I/F 204 illustrated in FIG. 3. Specifically, the NFC connection unit22 has a function that enables transmission and reception of informationconcerning connection conditions via wireless communication in order toestablish a connection between the Wi-Fi connection unit 21 and theimage processing apparatus 10 by using the pre-set connectionconditions.

The terminal-apparatus-side control unit 23, which is an example of aterminal-apparatus-side controller, controls the Wi-Fi connection unit21 and the NFC connection unit 22. According to the aforementioned NFCconnection handover technology, the terminal-apparatus-side control unit23 has a function for switching wireless communication from wirelesscommunication via the NFC connection unit 22 to wireless communicationvia the Wi-Fi connection unit 21. The terminal-apparatus-side controlunit 23 corresponds to a combination of the CPU 201 and the memory 202illustrated in FIG. 3.

The display unit 24 is a functional unit that displays an image andcorresponds to the image display unit 205 illustrated in FIG. 3.

Description Regarding Communication-Apparatus-Side Control Unit 13

The communication-apparatus-side control unit 13 will be described inmore detail.

First Exemplary Embodiment

First, the communication-apparatus-side control unit 13 according to afirst exemplary embodiment will be described.

In the first exemplary embodiment, in the case where the number ofconnections established for wireless communication via the Wi-Ficonnection unit 11 (i.e., the wireless communication I/F 110) hasreached the maximum number of connections allowed, thecommunication-apparatus-side control unit 13 transmits, via the NFCconnection unit 12 (i.e., the NFC I/F 111), information (warninginformation) indicating that wireless communication via the Wi-Ficonnection unit 11 (i.e., the wireless communication I/F 110) is notavailable to the mobile terminal 20 (i.e., the connection-requestingterminal apparatus) that attempts, via the NFC connection unit 12 (i.e.,the NFC I/F 111), to perform wireless communication via the Wi-Ficonnection unit 11 (i.e., the wireless communication I/F 110).

Specifically, the NFC connection unit 12 sets information indicatingthat Wi-Fi Direct is busy (the number of available connections=0) in amessage based on the NFC data exchange format (NDEF) used in NFCcommunication and transmits the NDEF message to the mobile terminal 20.

The NFC connection unit 22 (i.e., the NFC I/F 204) of the mobileterminal 20 receives this warning information. Then, theterminal-apparatus-side control unit 23 of the mobile terminal 20displays a message indicating, for example, “No Wi-Fi Direct connectionis currently available because all available Wi-Fi Direct connectionsare in use” on the display unit 24 (i.e., the image display unit 205).

In the related art, the warning information is not transmitted from theimage processing apparatus 10. Thus, the mobile terminal 20 is unable todetect a situation where no Wi-Fi Direct connection is available. Insuch a case, the mobile terminal 20 just displays, for example,“Connecting” on the display unit 24 (i.e., the image display unit 205),and a user of the mobile terminal 20 is kept waiting until a timeoutoccurs, for example.

In contrast, in the present exemplary embodiment, the warninginformation is transmitted from the image processing apparatus 10, andthe mobile terminal 20 displays a message based on this warninginformation on the display unit 24. Accordingly, the user friendlinessof the mobile terminal 20 improves.

Operations performed by the image processing apparatus 10 and the mobileterminal 20 according to the first exemplary embodiment will bedescribed next.

FIG. 5 is a flowchart describing operations performed by the imageprocessing apparatus 10 and the mobile terminal 20 in the firstexemplary embodiment.

The operations performed by the image processing apparatus 10 and themobile terminal 20 will be described below with reference to FIGS. 4 and5.

When a user wishes to print an image represented by print data stored inthe mobile terminal 20 by using the image processing apparatus 10, theuser goes to the location where the image processing apparatus 10 isinstalled and places the mobile terminal 20 (i.e., theconnection-requesting terminal apparatus) on the NFC connection unit 12(i.e., the NFC I/F 111) to cause the connection-requesting terminalapparatus to touch the NFC connection unit 12. In response to thisaction, NFC wireless communication is automatically initiated betweenthe NFC connection unit 22 (i.e., the NFC I/F 204) of theconnection-requesting terminal apparatus and the NFC connection unit 12.Then, information concerning connection conditions that are pre-set bythe connection-requesting terminal apparatus and that are used toestablish a connection to the Wi-Fi connection unit 11 (i.e., thewireless communication I/F 110) is transmitted and received.Consequently, the NFC connection unit 12 receives the informationconcerning connection conditions (step S101). At this time, the NFCconnection unit 12 of the image processing apparatus 10 operates in acard emulation mode and returns a response upon receipt of a dataacquisition request from the NFC connection unit 22 of theconnection-requesting terminal apparatus that operates in areader/writer mode. At this time, the information concerning connectionconditions is transmitted and received in accordance with the NDEF,which is a data format generally used in NFC communication.

At this time, the communication-apparatus-side control unit 13 of theimage processing apparatus 10 determines whether the number of Wi-FiDirect connections established has reached the maximum number ofconnections allowed (step S102).

If the number of Wi-Fi Direct connections established has not reachedthe maximum number of connections allowed (NO in step S102), thecommunication-apparatus-side control unit 13 transmits information usedto establish a Wi-Fi Direct connection to the connection-requestingterminal apparatus via the NFC connection unit 12 (step S103). Thisinformation is, for example, a MAC address or an SSID of the imageprocessing apparatus 10.

The NFC connection unit 22 of the connection-requesting terminalapparatus receives this information. The terminal-apparatus-side controlunit 23 then identifies a Wi-Fi Direct connection destination from thisinformation (step S104). Then, the terminal-apparatus-side control unit23 switches wireless communication from wireless communication via theNFC connection unit 22 to wireless communication via the Wi-Ficonnection unit 21 (i.e., the wireless communication I/F 203) (stepS105).

Then, the Wi-Fi connection unit 21 transmits a connection request to theWi-Fi connection unit 11. A connection is established between the Wi-Ficonnection unit 21 of the connection-requesting terminal apparatus andthe Wi-Fi connection unit 11 of the image processing apparatus 10 byusing the connection conditions. As a result, the connection-requestingterminal apparatus and the image processing apparatus 10 are connectedto each other by Wi-Fi Direct (step S106).

The user then operates the connection-requesting terminal apparatus orthe image processing apparatus 10 to input an instruction to cause theimage processing apparatus 10 to perform printing. As a result, imagedata is transmitted from the Wi-Fi connection unit 21 to the Wi-Ficonnection unit 11 by using Wi-Fi Direct, and printing is performed bythe image forming unit 14 of the image processing apparatus 10 (stepS107).

After printing has been finished, the user removes or detaches theconnection-requesting terminal apparatus from the NFC connection unit 12(i.e., the NFC I/F 111). As a result, the NFC connection unit 12 and theconnection-requesting terminal apparatus are no longer able towirelessly communicate with each other. Thus, thecommunication-apparatus-side control unit 13 disconnects the Wi-FiDirect connection that has been established between theconnection-requesting terminal apparatus and the image processingapparatus 10 (step S108). The connection may be disconnected when theprinting is finished.

If the number of Wi-Fi Direct connections established has reached themaximum number of connections allowed (YES in step S102), the imageprocessing apparatus 10 transmits, to the connection-requesting terminalapparatus via the NFC connection unit 12, information containing warninginformation which indicates that Wi-Fi Direct wireless communication isnot available (step S109).

The NFC connection unit 22 of the connection-requesting terminalapparatus receives this information containing the warning information(step S110). The terminal-apparatus-side control unit 23 of theconnection-requesting terminal apparatus then displays a messageindicating “No Wi-Fi Direct connection is available” on the display unit24 (i.e., the image display unit 205) (step S111).

Second Exemplary Embodiment

The communication-apparatus-side control unit 13 according to a secondexemplary embodiment will be described next.

In the second exemplary embodiment, the communication-apparatus-sidecontrol unit 13 performs a reservation process so as to allow theconnection-requesting terminal apparatus to preferentially use a linefor (Wi-Fi Direct) wireless communication via the Wi-Fi connection unit11 when the line becomes available after transmitting the warninginformation.

In the case where the mobile terminal 20 (i.e., theconnection-requesting terminal apparatus) attempts, via the NFCconnection unit 12, to establish a connection to the image processingapparatus 10, a user of the mobile terminal 20 is in front of the imageprocessing apparatus 10. That is, it is highly likely that the userwishes to use the image processing apparatus 10 immediately andurgently. Thus, the user is desirably prioritized and allowed to use theimage processing apparatus 10. In the related art, however, when thenumber of Wi-Fi Direct connections established has reached the maximumnumber of connections allowed, the user is required to manually causethe connection-requesting terminal apparatus to touch the NFC connectionunit 12 (i.e., the NFC I/F 111) again and again until a Wi-Fi Directcommunication line becomes available as a result of disconnection of aconnection between another mobile terminal 20 and the image processingapparatus 10. In addition, even if a line becomes available, anothermobile terminal 20 sometimes establishes a connection to the imageprocessing apparatus 10 before the connection-requesting terminalapparatus does.

Accordingly, in the present exemplary embodiment, the reservationprocess is performed so as to allow the connection-requesting terminalapparatus that uses the NFC connection unit 12 to preferentially use theline when a line becomes available. With the reservation process, asituation where another terminal apparatus 20 establishes a connectionto the image processing apparatus 10 before the connection-requestingterminal apparatus does is avoided.

Operations performed by the image processing apparatus 10 and the mobileterminal 20 according to the second exemplary embodiment will bedescribed next.

FIG. 6 is a flowchart describing operations performed by the imageprocessing apparatus 10 and the mobile terminal 20 in the secondexemplary embodiment.

The operations performed by the image processing apparatus 10 and themobile terminal 20 will be described below with reference to FIGS. 4 and6.

Because steps S201 to S208 of FIG. 6 are similar to steps S101 to S108of FIG. 5, a description thereof is omitted and a description startsfrom step S209.

If the number of connections established has reached the maximum numberof connections allowed (YES in step S202), thecommunication-apparatus-side control unit 13 performs theabove-described reservation process (step S209). The reservation processuses identification information of the connection-requesting terminalapparatus, such as the MAC address or the serial number of theconnection-requesting terminal apparatus. Such information may beacquired when information concerning connection conditions istransmitted and received in step S201.

Steps S210 to S212 are similar to steps S109 to S111 of FIG. 5.

After step S212, the communication-apparatus-side control unit 13monitors whether a line becomes available as a result of disconnectionof a Wi-Fi Direct connection between another mobile terminal 20 and theimage processing apparatus 10 (step S213).

If there is no available line (NO in step S213), thecommunication-apparatus-side control unit 13 monitors whether wirelesscommunication with the connection-requesting terminal apparatus via theNFC connection unit 12 is continued (step S214). If there is noavailable line, the terminal-apparatus-side control unit 23 of theconnection-requesting terminal apparatus may display a messageindicating, for example, “Wi-Fi Direct connection is busy. Please waitfor a while. Processing will continue upon finding an available line.”on the display unit 24 (i.e., the image display unit 205).

If the wireless communication with the connection-requesting terminalapparatus via the NFC connection unit 12 is continued (YES in stepS214), the process returns to step S213.

If the wireless communication with the connection-requesting terminalapparatus is no longer performed (NO in step S214), thecommunication-apparatus-side control unit 13 cancels the reservation(step S215). That is, this case corresponds to the case where the userhas removed and detached the connection-requesting terminal apparatusfrom the NFC connection unit 12 (i.e., the NFC I/F 111). In this case,it is considered that the user no longer wishes to perform printingusing the image processing apparatus 10, and thus the reservation is nolonger needed.

If a line becomes available (YES in step S213), thecommunication-apparatus-side control unit 13 transmits, to theconnection-requesting terminal apparatus using the NFC connection unit12, information indicating that a Wi-Fi Direct line has becomeavailable. The process then proceeds to step S203, and printing isperformed by the image forming unit 14 of the image processing apparatus10. In the case where a connection request is received from anothermobile terminal 20, the communication-apparatus-side control unit 13rejects the connection request. Whether the sender of the connectionrequest is the connection-requesting terminal apparatus or anothermobile terminal 20 is identifiable based on the identificationinformation.

Third Exemplary Embodiment

The communication-apparatus-side control unit 13 according to a thirdexemplary embodiment will be described next.

In the second exemplary embodiment, the user is required to be in frontof the image processing apparatus 10 and to keep theconnection-requesting terminal apparatus touching the NFC connectionunit 12 (i.e., the NFC I/F 111) until a Wi-Fi Direct line becomesavailable. In this case, other users recognize that the image processingapparatus 10 is currently reserved by seeing the user who is in front ofthe image processing apparatus 10; however, it is often inconvenientthat the user is unable to leave the image processing apparatus 10.

In contrast to the second exemplary embodiment, the third exemplaryembodiment allows the user to detach the connection-requesting terminalapparatus from the NFC connection unit 12 (i.e., the NFC I/F 111) andleave the image processing apparatus 10 under a specific condition.

In the third exemplary embodiment, the communication-apparatus-sidecontrol unit 13 receives a connection request from theconnection-requesting terminal apparatus via Wi-Fi Direct atpredetermined intervals T after the preservation process has beenperformed for the connection-requesting terminal apparatus. Then, when aline becomes available, the communication-apparatus-side control unit 13allows this connection-requesting terminal apparatus to preferentiallyuse the line.

In this case, a connection request is received not by NFC but by Wi-FiDirect. Thus, the user is permitted to detach the connection-requestingterminal apparatus from the NFC connection unit 12 (i.e., the NFC I/F111) and leave the image processing apparatus 10. The reservation ismaintained if the user is within a communication range of Wi-Fi Direct.When a Wi-Fi Direct line becomes available, the connection-requestingterminal apparatus preferentially uses this line.

Operations performed by the image processing apparatus 10 and the mobileterminal 20 according to the third exemplary embodiment will bedescribed next.

FIG. 7 is a flowchart describing operations performed by the imageprocessing apparatus 10 and the mobile terminal 20 in the thirdexemplary embodiment.

The operations performed by the image processing apparatus 10 and themobile terminal 20 will be described below with reference to FIGS. 4 and7.

Because steps S301 to S312 of FIG. 7 are similar to step S201 to S212 ofFIG. 6, a description thereof is omitted and a description starts fromstep S313.

After step S312, the terminal-apparatus-side control unit 23 of theconnection-requesting terminal apparatus switches wireless communicationfrom wireless communication via the NFC connection unit 22 to wirelesscommunication via the Wi-Fi connection unit 21 (step S313).

The terminal-apparatus-side control unit 23 of the connection-requestingterminal apparatus then transmits, using the Wi-Fi connection unit 21, aconnection request to the image processing apparatus 10 at predeterminedintervals T (step S314). That is, the connection-requesting terminalapparatus keeps performing a connection retry to the image processingapparatus 10. The predetermined interval T may be acquired from theimage processing apparatus 10 when information concerning connectionconditions is transmitted and received in step S301. At this time, theconnection-requesting terminal apparatus and the image processingapparatus 10 are not connected by Wi-Fi Direct but the connectionrequest is received by the Wi-Fi connection unit 11 of the imageprocessing apparatus 10 even in such a state.

The communication-apparatus-side control unit 13 monitors whether a linebecomes available as a result of disconnection of a Wi-Fi Directconnection between another mobile terminal 20 and the image processingapparatus 10 (step S315).

If there is no available line (NO in step S315), thecommunication-apparatus-side control unit 13 of the image processingapparatus 10 monitors whether a connection request is received from theconnection-requesting terminal apparatus at the predetermined intervalsT (step S316).

If a connection request is no longer received from theconnection-requesting terminal apparatus at the predetermined intervalsT (NO in step S316), the communication-apparatus-side control unit 13cancels the reservation (step S317). That is, this case corresponds tothe case where the user has left the communication range of Wi-FiDirect, and it is considered that the user no longer wishes to performprinting using the image processing apparatus 10. In such a case, aconnection request is no longer received from the connection-requestingterminal apparatus, and thus the reservation is canceled. Note that thecommunication-apparatus-side control unit 13 determines that aconnection request is no longer received at the predetermined intervalsT in the case where a connection request is not received within a timeperiod T+α (where, α is a predetermined time period) from the lastconnection request, for example.

If a connection request is received at the predetermined intervals T(YES in step S316), the process returns to step S315.

If a line becomes available (YES in step S315), thecommunication-apparatus-side control unit 13 transmits, to theconnection-requesting terminal apparatus using the Wi-Fi connection unit11, information indicating that a Wi-Fi Direct line has becomeavailable. The process then proceeds to step S306, and printing isperformed by the image forming unit 14 of the image processing apparatus10. The information indicating that a Wi-Fi Direct line has becomeavailable may be transmitted as a response to a connection request fromthe connection-requesting terminal apparatus. In the case where aconnection request is received from another mobile terminal 20, thecommunication-apparatus-side control unit 13 rejects the connectionrequest. Whether the sender of the connection request is theconnection-requesting terminal apparatus or another mobile terminal 20is identifiable based on the identification information.

Fourth Exemplary Embodiment

The communication-apparatus-side control unit 13 according to a fourthexemplary embodiment will be described next.

In the fourth exemplary embodiment, the communication-apparatus-sidecontrol unit 13 disconnects a wireless connection to the connectedmobile terminal 20 in accordance with a predetermined rule. In this way,the communication-apparatus-side control unit 13 prepares a lineconnected preferentially to the connection-requesting terminal apparatuswhen the number of connections established for (Wi-Fi Direct) wirelessconnection via the Wi-Fi connection unit 11 has reached the maximumnumber of connections allowed.

Examples of the predetermined rule include the following conditions (1)to (4). The communication-apparatus-side control unit 13 selects themobile terminal 20 that satisfies any one of the conditions anddisconnects the connection to the selected mobile terminal 20.

(1) A mobile terminal 20 that does not use a print job transfer protocolin communication, that is, a mobile terminal 20 that is not transferringprint data of a print job

(2) A mobile terminal 20 that has the minimum amount of data exchangedvia communication during a past predetermined period

(3) A mobile terminal 20 that has the oldest Wi-Fi Direct connectionstart time

(4) A mobile terminal 20 that has the longest no-communication period upto the present time point

The conditions (1) to (4) allow selection of the mobile terminal 20 forwhich the influence of disconnection of a Wi-Fi Direct connection isminimal. Note that the communication-apparatus-side control unit 13 maynotify the disconnection-target mobile terminal 20 of disconnection.

As described above, in the fourth exemplary embodiment, a line connectedpreferentially to the connection-requesting terminal apparatus that hasa high urgency and that is desirably prioritized and allowed to use theimage processing apparatus 10 is prepared.

Operations performed by the image processing apparatus 10 and the mobileterminal 20 according to the fourth exemplary embodiment will bedescribed next.

FIG. 8 is a flowchart describing operations performed by the imageprocessing apparatus 10 and the mobile terminal 20 in the fourthexemplary embodiment.

The operations performed by the image processing apparatus 10 and themobile terminal 20 will be described below with reference to FIGS. 4 and8.

Because steps S401 to S408 of FIG. 8 are similar to steps S101 to S108of FIG. 5, a description thereof is omitted and a description startsfrom step S409.

If the number of connections established has reached the maximum numberof connections allowed (YES in step S402), thecommunication-apparatus-side control unit 13 selects, from among themobile terminals 20 that are already connected to the image processingapparatus 10, the mobile terminal 20 that satisfies any of theconditions (1) to (4) (step S409).

The communication-apparatus-side control unit 13 then disconnects aWi-Fi Direct connection to the selected mobile terminal 20 (step S410).

The process then proceeds to step S403, and printing is performed by theimage forming unit 14 of the image processing apparatus 10.

In the exemplary embodiments described in detail above, wirelesscommunication is performed between the mobile terminal 20 and the imageprocessing apparatus 10 by using Wi-Fi Direct. However, the wirelesscommunication scheme is not limited to this particular scheme, and anywireless communication scheme with a limited number of allowedconnections may be used.

In addition, in the exemplary embodiments described in detail above, themobile terminal 20 performs wireless communication by using Wi-FiDirect. However, the apparatus is not limited to the mobile terminal 20,and the operation terminal 30 (see FIG. 1) may perform wirelesscommunication.

Further, in the exemplary embodiments described in detail above, theimage processing apparatus 10 that forms an image serves as acommunication apparatus according to the exemplary embodiments. However,the communication apparatus is not limited to the image processingapparatus 10 and may be an apparatus of another type.

While the exemplary embodiments have been described above, the technicalscope of the present invention is not limited to the scope of theabove-described exemplary embodiments. It is obvious from the attachedclaims that embodiments obtained by making various alterations andimprovements to the exemplary embodiments are also within the technicalscope of the present invention.

The foregoing description of the exemplary embodiments of the presentinvention has been provided for the purposes of illustration anddescription. It is not intended to be exhaustive or to limit theinvention to the precise forms disclosed. Obviously, many modificationsand variations will be apparent to practitioners skilled in the art. Theembodiments were chosen and described in order to best explain theprinciples of the invention and its practical applications, therebyenabling others skilled in the art to understand the invention forvarious embodiments and with the various modifications as are suited tothe particular use contemplated. It is intended that the scope of theinvention be defined by the following claims and their equivalents.

What is claimed is:
 1. A communication apparatus comprising: a firstcommunication unit that wirelessly communicates with a plurality ofterminal apparatuses, the number of which is less than or equal to apredetermined maximum number of connections allowed; a secondcommunication unit that wirelessly communicates with aconnection-requesting terminal apparatus that attempts to wirelesslycommunicate with the first communication unit; and acommunication-apparatus-side controller that transmits, to theconnection-requesting terminal apparatus via the second communicationunit, information indicating that wireless communication via the firstcommunication unit is not available in a case where the number ofconnections established for wireless communication via the firstcommunication unit has reached the predetermined maximum number ofconnections allowed.
 2. The communication apparatus according to claim1, wherein in a case where the communication-apparatus-side controllertransmits the information indicating that wireless communication via thefirst communication unit is not available, thecommunication-apparatus-side controller performs a reservation processso as to allow the connection-requesting terminal apparatus topreferentially use a line for wireless communication via the firstcommunication unit when the line becomes available.
 3. The communicationapparatus according to claim 2, wherein the communication-apparatus-sidecontroller cancels a reservation in a case where the secondcommunication unit is no longer able to wirelessly communicate with theconnection-requesting terminal apparatus.
 4. The communication apparatusaccording to claim 2, wherein the first communication unit receives aconnection request from the connection-requesting terminal apparatus atpredetermined intervals, and the communication-apparatus-side controllercancels a reservation in a case where the connection request is nolonger received from the connection-requesting terminal apparatus at thepredetermined intervals.
 5. A communication apparatus comprising: afirst communication unit that wirelessly communicates with a pluralityof terminal apparatuses, the number of which is less than or equal to apredetermined maximum number of connections allowed; a secondcommunication unit that wirelessly communicates with aconnection-requesting terminal apparatus that attempts to wirelesslycommunicate with the first communication unit; and acommunication-apparatus-side controller that disconnects a connectionestablished to wirelessly communicate with an already connected terminalapparatus in accordance with a predetermined rule and prepares a line towhich the connection-requesting terminal apparatus is preferentiallyconnected, in a case where the number of connections established forwireless communication via the first communication unit has reached thepredetermined maximum number of connections allowed.
 6. A terminalapparatus comprising: a third communication unit that transmits andreceives information to and from a communication apparatus via awireless communication network for which a maximum number of connectionsallowed is predetermined; a fourth communication unit that wirelesslycommunicates with the communication apparatus when the terminalapparatus attempts to perform wireless communication via the thirdcommunication unit; and a terminal-apparatus-side controller thatswitches wireless communication performed via the fourth communicationunit to wireless communication performed via the third communicationunit, wherein the fourth communication unit receives informationindicating that wireless communication via the third communication unitis not available from the communication apparatus in a case where thenumber of connections established in the wireless communication networkhas reached the maximum number of connections allowed.
 7. An imageprocessing system comprising: an image processing apparatus that formsan image; and terminal apparatuses each of which transmits, via wirelesscommunication, image information used by the image processing apparatusto form an image, the image processing apparatus including a firstcommunication unit that wirelessly communicates with a plurality ofterminal apparatuses, the number of which is less than or equal to apredetermined maximum number of connections allowed, among the terminalapparatuses, a second communication unit that wirelessly communicateswith a connection-requesting terminal apparatus that attempts towirelessly communicate with the first communication unit, among theterminal apparatuses, a communication-apparatus-side controller thattransmits, to the connection-requesting terminal apparatus via thesecond communication unit, information indicating that wirelesscommunication via the first communication unit is not available in acase where the number of connections established for wirelesscommunication via the first communication unit has reached thepredetermined maximum number of connections allowed, and an imageforming unit that forms an image.
 8. A communication method comprising:wirelessly communicating, via a second communication unit, with aconnection-requesting terminal apparatus that attempts to wirelesslycommunicate with a first communication unit which wirelesslycommunicates with a plurality of terminal apparatuses, the number ofwhich is less than or equal to a predetermined maximum number ofconnections allowed; and transmitting, to the connection-requestingterminal apparatus via the second communication unit, informationindicating that wireless communication via the first communication unitis not available in a case where the number of connections establishedfor wireless communication via the first communication unit has reachedthe predetermined maximum number of connections allowed.